A powerful nor'easter with blinding snow and bitter winds bore down on the tri-state Friday, forcing flight cancellations, the shutdown of highways and the New York City public school system, and causing major reductions in mass transit service as wind-whipped powder piled up on sidewalks and streets.

The snow tapered off by midday Friday, but the blustery, numbing winds stuck around, causing more localized blowing and drifting of powdery snow.

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A state of emergency was declared in New York and New Jersey ahead of the storm that dumped 10 inches of snow on parts of New York City, more than a foot in parts of Long Island and 8 inches or more in New Jersey and Connecticut.

The storm brought icy high tides to coastal areas of New Jersey. Police in Monmouth Beach said three people, including a mailman, were rescued after their vehicles hit high water on low roads.

The Long Island Expressway was closed at midnight Friday as rapid snowfall combined with winds gusting up to 35 miles per hour to create white-out conditions, severely hampering visibility. The highway reopened around 8 a.m.

New York City schools are closed Friday, according to the city Department of Education. Central and field offices will be open. After-school programs, PSAL games and class trips are also canceled. A full list of other school closures can be seen here.

The Long Island Expressway reopened at 8 a.m. in Nassau and Suffolk counties after an eight-hour closure. Interstate 84 was also closed until 8 a.m. in New York. Interstate 87 south of Albany reopened to all vehicles at 8 a.m.

John F. Kennedy International Airport reopened shortly before 10:30 a.m. after being shut down for hours due to low visibility, according to the FAA. Hundreds of flights have been canceled at New York's three major airports.

Amtrak said it will be operating on a modified schedule on Friday.

Newark City Hall and Municipal Court are both closed Friday. All non-emergency services have been suspended in the city.

In New York City, the Department of Transportation announced that alternate-side parking regulations would be suspended as sanitation crews salt and clear the streets. Parking meter rules remain in effect. Residents can track snow removal progress in their neighborhood at PlowNYC.

Express subway service ended Thursday evening as cars were moved onto express tracks overnight. Local service will continue on the entire subway system through the start of rush hour Friday until trains can be moved off express tracks.

Metro-North and the Long Island Rail Road both will run on Saturday schedules on Friday. As a result, there will be no train service on the LIRR's West Hempstead branch or east of Ronkonkoma on the Ronkonkoma branch. Substitute bus service between Ronkonkoma and Greenport will be provided.

Buses will be chained, and extra drivers are being brought in to cover the storm, the MTA says. If roads become impassable, bus service will be suspended. Stay updated on MTA service here.